POST UTME AFE BABALOLA UNIVERSITY 2021 Chemistry | Objective

Practice these randomly selected questions to test your readiness.

Question 1
Calculate the s\tandard enthalpy change (ΔH⁰) for the reaction: 2Al(s) + 6HCl(aq) → 2AlCl3(aq) + 3H2(g). The s\tandard enthalpy of formation (ΔH⁰f) values are: Al(s) = 0 kJ/mol, HCl(aq) = -92.3 kJ/mol, AlCl3(aq) = -704.0 kJ/mol, H2(g) = 0 kJ/mol. Assume the reaction is carried out at 298 K.
A. -1768.6 kJ/mol
B. -704.0 kJ/mol
C. -92.3 kJ/mol
D. -704.0 kJ/mol + 2\( 0 kJ/mol \)
Question 2
A reaction has an activation energy of 100 kJ/mol and a rate cons\tant of 0.1 s^-1 at 300 K. Calculate the frequency factor (A) for the reaction.
A. 1 x 10^10 s^-1
B. 1 x 10^12 s^-1
C. 1 x 10^14 s^-1
D. 1 x 10^16 s^-1
Question 3
A polymer has the following structure: [-CH2-CH2-CH2-CH2-]n. What is the type of polymerization reaction that produced this polymer?
A. Addition polymerization
B. Condensation polymerization
C. Ring-opening polymerization
D. Step-growth polymerization
Question 4
A 2.00 g sample of a polymer is dissolved in 50.0 mL of a solvent. If the density of the solution is 1.05 g/mL, what is the molar mass of the polymer?
A. 1000 g/mol
B. 2000 g/mol
C. 5000 g/mol
D. 10,000 g/mol
Question 5
A 0.1 M solution of a weak base, B, has a pH of 9.25. Calculate the value of Kb for the base.
A. 1.8 x 10^\( -5 \)
B. 2.0 x 10^\( -5 \)
C. 2.5 x 10^\( -5 \)
D. 3.0 x 10^\( -5 \)
Question 6
A 1.0 M solution of a weak acid, HA, has a pH of 4.25. Calculate the value of Ka for the acid.
A. 1.8 x 10^\( -5 \)
B. 2.0 x 10^\( -5 \)
C. 2.5 x 10^\( -5 \)
D. 3.0 x 10^\( -5 \)
Question 7
A 2.0 g sample of a polymer is dissolved in 100 mL of solvent. Calculate the molar mass of the polymer.
A. 500 g/mol
B. 600 g/mol
C. 700 g/mol
D. 800 g/mol
Question 8
What is the major product of the reaction between ethene and HBr?
A. 1-bromoethane
B. 2-bromoethane
C. 1-bromoethane
D. 2-bromoethane
Question 9
The s\tandard enthalpy of formation (ΔH⁰f) of H2(g) is 0 kJ/mol. Calculate the s\tandard enthalpy of combustion (ΔH⁰c) of 1.00 mol of H2(g) u\sing the following equation: 2H2(g) + O2(g) → 2H2O(l).
A. -285.8 kJ/mol
B. -285.8 kJ/mol + 0 kJ/mol
C. -285.8 kJ/mol + 0 kJ/mol
D. -285.8 kJ/mol + 0 kJ/mol
Question 10
The following diagram shows a titration setup. Identify the part labeled A.
A. Burette
B. Beaker
C. Test tube
D. Circuit
Question 11
A 2.00 g sample of a polymer is dissolved in 50.0 mL of a solvent. If the density of the solution is 1.05 g/mL, what is the molar mass of the polymer?
A. 1000 g/mol
B. 2000 g/mol
C. 5000 g/mol
D. 10,000 g/mol
Question 12
A sample of $\text{CaCO}_3$ weighing 25.0 g is heated to produce $\text{CaO}$ and $\text{CO}_2$. If the mass of $\text{CaO}$ produced is 17.0 g, what is the mass of $\text{CO}_2$ produced?
A. 4.0 g
B. 6.0 g
C. 8.0 g
D. 10.0 g
Question 13
The following diagram shows a cell. Identify the part labeled A.
A. Cell membrane
B. Cytoplasm
C. Nucleus
D. Mitochondria
Question 14
What is the major product of the reaction between 2-methylpropane and chlorine?
A. 2-chloro-2-methylpropane
B. 2,2-dichloro-2-methylpropane
C. 2-chloro-2-methylpropane
D. 2,2-dichloro-2-methylpropane
Question 15
Determine the number of stereocenters in the following compound: [CH_3CH(OH)CH_2CH_3]
A. 1
B. 2
C. 3
D. 4

Master the Exam!

You've seen a preview, but there are thousands more questions plus AI tutor to break down complex solutions.

Unlock Full Access Available for Android & Windows
Help others prepare! Share this practice hub: